In the past, laundry sorting in commercial facilities has required either a great deal of manual labor or fairly complicated equipment.
The commercial laundering and cleaning of articles, particularly in the linen supply field, require an accurate count of the number of articles being handled. The methods presently employed for counting articles vary from strictly manual sorting and counting to sophisticated devices which automatically sense, differentiate and count different types of articles based upon the presence of markers or tags on the articles.
Strictly hand-processing of laundry is the least attractive method. The workers employed for such tasks typically have low-skill levels and low interest in maintaining accurate counts. Inaccurate counts lead to inventory losses and customer dissatisfaction.
At the other extreme, certain sophisticated systems exist for essentially automatically processing pieces of laundry. All such systems require the provision of some type of a coding tag on the individual laundry pieces which can be detected by an appropriate sensor scanning each of the pieces as it is passed by the sensor.
One of the disadvantages of this type of system is that a marker must be provided on each laundry piece. This can be an expensive proposition where literally hundreds of thousands of pieces of inventory are involved. It may also not be a viable form of operation for commercial laundries serving retail laundry and cleaning establishments where privately-owned pieces of laundry are serviced. Each piece would require a tag. The tags either would have to be removed at the completion of processing, a significant labor cost, or, more likely, would not be removed and would be lost when the pieces were not returned for further cleaning. Another disadvantage is that even with such automatic counting systems, manual labor must still be employed to separate the pieces of laundry being fed past the sensors so that the sensors are not simultaneously confronted with multiple tags.
A less sophisticated type of automated counting system utilizes multiple belts on a 30 to 45 degree angle. Photoelectric eyes, or reed-type switches, are then used to count the articles as they pass up the belts. The materials-handling aspect of this type of system is one of its major weaknesses. Textile articles like linens have a tendency to roll back down the belts if the system is installed to accommodate tall cylindrical slings. Many times linens will jam on the dividing walls between the different lanes. The next piece of linen thrown down that lane will dislodge the jammed item, only to be miscounted as the piece goes through the counters as one piece. Often, the slings or carts will fill up, only to be ignored by the operator. This can cause a back-up on the belts, thus blocking the counting device. When the lane is cleared, or the sling moved, all linens then go into the new sling and are not counted.
A third approach has been to use a light frame. An operator selects articles of a single category (e.g. napkins or hand towels) from a load of mixed articles and throws them sequentially through the light frame which, with associated circuitry, registers and accumulates a count of the articles As each category is separated from the load and counted, the accumulated counts are noted.
One problem associated with light frame systems is the tendency for double counting. The frames typically employ a number of individual light beams, one or more of which may be broken at separate times by different portions of a single article thrown through the frame. Other sources of double counts arising with such frames are flying insects which may be attracted to dirty laundry and pieces of debris sometimes present with the laundry and thrown with the articles.
To prevent double counting, such systems typically have circuitry to provide a time delay between counts. However, the delay must be varied for individual pieces of laundry of different sizes and/or types. Thus, the delay for small pieces like hand towels and napkins is smaller than the delay used for larger pieces such as towels and still different from the delay needed for extremely large pieces such as sheets, tablecloths and blankets.
Another problem associated with light frame systems is that the operator must actually throw each article through the light frame with at least a minimum velocity. This is to insure that the programmed time delay is not exceeded and the pieces double counted. It is also necessary in commercial cleaning establishments to process the large numbers of laundry pieces which such establishments normally handle. This is extremely tiring work in the best of circumstances. Exhaustion of an operator towards the end of the shift can result in pieces being thrown insufficiently fast through the light frame and double counts occurring.
It would be very beneficial to provide a system and method for counting individual textile articles like pieces of laundry which do not require the use of special markers on the articles.
It would also be very beneficial to provide an apparatus and method for counting individual textile articles which is less prone to counting errors than are light frame and manual counting systems which do not use special markers or tags on each article.
It would be very beneficial to provide an apparatus and method for counting textile articles which minimizes double counts and missed counts.
It would further be beneficial to provide a method and apparatus for moving textile articles such as pieces of laundry, whether for counting purposes or otherwise, which is less physically taxing on the operators.